I have a question: I have a DW-7000 double. That model uses chains. I've owned it for 5 years, and I am ashamed to say I have never oiled the chain, though I should mention it is my practice pedal so it stays stationary in a temperature controlled room, but no excuses nonetheless.

Anyway, it has developed a bit of a squeak and I am wondering if oiling it with WD-40 would restore it, or if it's pretty much too late since I let it go this long?

Remove the chain from the pedal.
Put some automotive Automatic Transmission Fluid or light Hydraulic Oil in a small pan.
Coil the chain up and stir it around in the fluid for a while. Then soak it overnight.
Wipe off the excess fluid and the chain will be clean, rust free, and lubed.

ATF is a great solvent. I have been using it to clean things for many years.
I learned about the cleaning properties of ATF from working in a transmission repair shop.
My tools would always be clean and rust free from being exposed to the fluid.
There would be no dirt under my fingernails at the end of the day.
It is designed to be both a solvent and a lubricant inside of a transmission.
There are also products for cleaning bicycle and motorcycle chains that are similar.

The bearings and hinges on the pedal can also squeak. There are vids on YouTube that show how to clean and lube them.
They can be soaked and cleaned the same way as the chain.

WD40 is a penetrant de greaser more than a lubricant. A Teflon based lubricant is better for pedal chains.

+1^ This.The WD in WD 40 stands for water displacement,and it's more suited as a moisture barrier,than a lubricant.Powdred teflon is much better suited fot the job of lubricating contact areas of a foot pedal and stands up to heat better and longer.It's also not a lint collector.

tamadrm & mikel, WD-40 is an excellent lubricant.
Did you read the link that I posted?
WD-40 was developed by the aerospace industry to protect and lubricate air and spacecraft parts before, during, and after assembly.

I don't imagine it's as much of a problem with bass drum pedals as it is with motorcycles, but chains can also wear over time. The wear causes stretch, looseness, and sloppiness in general. There are ways to check for wear.

Altho the WD 40 guys crow about the product being an excellent lube...

WD-40 and Bike's
Myth: WD-40 Multi-Use Product should not be used on bike chains.
Fact:
While WD-40 Multi-Use Product it is not a grease, it is formulated with strong lubricating oils and other ingredients, and is a terrific product to use for bike maintenance. It does not attract dirt or moisture to metal surfaces – just be sure to wipe off any excess WD-40 Multi-Use Product before riding.

they do admit it has no lasting power and were sooo not able to dodge the fact they had to create a new product, WD FARTY BIKE. Read the key words 'long-term'.

For long-term lubrication and other specialized bicycle maintenance needs, check out WD-40® BIKE. Developed specifically for cyclists and mechanics, this high-performance line of bicycle care products is sure to become a mainstay in the toolboxes of bike mechanics for decades.

So yeah, don't use regular WD 40 as a lube, unless you want to do it often.

You were missing that info Bo, Chains get dirty, rusty, and sticky if they are not cared for properly.

Ah. Understood. I can see this being necessary on pedals that actually use a sprocket too, but lately, alot of pedals have chains, but they're not mounted on a sprocket. In fact, my Yamaha pedal has a chain, but it fits in the same trough that uses the strap, but it sits on felt and never sees gear teeth.

Since its been so long that you haven't lubed them, I'd soak them in WD-40 for a little while. Then after wiping them off a bit, put some sowing machine oil on them. It's cheap and works great. I use a belt drive pedal these days - much better in my opinion. But when I used chain drive pedals I went with sowing machine oil.